Combustor

Abstract

A combustor includes a first wall, a second wall, an injector grommet, a combustor longitudinal axis, and a connection assembly indirectly connecting the first wall to the second wall. A portion of the injector grommet is disposed within a groove of the connection assembly.

1. A combustor for a gas turbine engine comprising:
 a plurality of liners to define a substantially enclosed space where combustion of a fuel-air mixture takes place, the liners defining an open aft end where hot gases from the combustion escape the combustor at high speeds and, are directed toward a turbine; 
 the plurality of liners including at least a first dome and a second dome one of the first dome or the second dome having a plurality of impingement-holes to allow cooling air to pass through and impinge on the other of the first dome or the second dome; 
 a connection assembly positioned between the first dome and the second dome the connection assembly defining an opening in which a fuel injector may be positioned to inject a fuel-air mixture into the substantially enclosed space for combustion, the second dome being directly fixed to the connection assembly, the first dome being retained in a groove formed in the connection assembly, the groove and the first dome defining a non-uniform gap therebetween so that the first dome through thermal expansion is permitted to move relative to the second dome in an aligned radial direction, but is not permitted to move relative to the second dome in any other direction. 
 
     
     
       2. The combustor of  claim 1  further comprising an injector grommet that is positioned within an inner groove formed in the connection assembly with a sliding fit. 
     
     
       3. The combustor of  claim 1  further comprising a plurality of impingement holes formed through the connection assembly to permit cooling air to pass therethrough and impinge upon and cool the hot dome. 
     
     
       4. A combustor for a gas turbine engine comprising:
 an annular inner hot liner, an annular outer hot liner, and a hot dome connecting the inner hot liner to the outer hot liner and each being formed around a combustor longitudinal axis, the inner hot liner, outer hot liner, and the hot dome defining an annularly-shaped, partially enclosed area where a fuel-air mixture can burn, and further defining an aft end opening opposite the hot dome where the hot gas products of the combustion can escape and can be directed against a turbine; 
 an annular inner cold liner, an annular outer cold liner, and a cold dome connecting the inner cold liner to the outer cold liner and each being formed around the combustor longitudinal axis, the inner hot liner, outer hot liner, and cold dome substantially surrounding and enclosing the inner hot liner, the outer hot liner, and the hot dome and defining a channel therebetween for cooling air flow, the inner cold liner, outer cold liner, and the cold dome each including impingement holes that permit cooling air to flow therethrough and impinge upon the inner hot liner, the outer hot liner, and the hot dome; 
 the inner hot liner and the inner cold liner are connected near the aft end opening, and the outer hot liner and the outer cold liner are connected near the aft end opening; 
 a connection assembly joining the hot dome and the cold dome and defining an opening through each in which a fuel injector may be positioned to direct a fuel-air mixture into the enclosed area where the fuel-air mixture can burn, the connection assembly permitting the hot dome to move relative to the cold dome in an aligned radial direction that is normal to and toward and away from the longitudinal combustor axis, and prohibiting the hot dome to move relative to the cold dome in any other direction. 
 
     
     
       5. The combustor of  claim 4  wherein a portion of one of the hot dome or the cold dome is positioned within an annular groove formed in the connecting assembly, and the groove is non-circular. 
     
     
       6. The combustor of  claim 5  wherein the groove and the portion of the hot dome or the cold dome positioned therein form a non-uniform gap therebetween. 
     
     
       7. The combustor of  claim 6  wherein the non-uniform gap is larger in width in the aligned radial direction that it is in any other direction. 
     
     
       8. The combustor of  claim 4  further comprising an injector grommet that is positioned within an inner groove formed in the connection assembly with a sliding fit. 
     
     
       9. The combustor of  claim 4  further comprising a plurality of impingement holes formed through the connection assembly to permit cooling air to pass therethrough and impinge upon and cool the hot dome.